Manga Extras? , help

[laury_kos]

Hello there!

I've been re-reading the manga at MangaReader
But I can see that they are missing the extra chapters and since it's been a while , I really don't know where to look for them...

Anyone knows? Where can I read them or download them?
I'll be eternally grateful! (I'm sure I won't be the only one)

Thanks in advance!